Separator for non-aqueous electrolyte battery, and non-aqueous electrolyte battery

Abstract

The present invention provides a separator for a non-aqueous electrolyte battery that includes a porous base material including a polyolefin and a heat-resistant porous layer provided on at least one surface of the porous base material and including a heat-resistant resin, in which when a thermomechanical analysis measurement has been performed by applying a constant load, the separator for a non-aqueous electrolyte battery satisfies the following conditions (i) and (ii): (i) at least one shrinkage peak appears in a temperature range of from 130 to 155° C. in a displacement waveform representing shrinkage displacement with respect to temperature; and (ii) an extension rate in a range from a shrinkage peak appearance temperature T 1 to (T 1 +20)° C. is less than 0.5%/° C.

1 . A separator for a non-aqueous electrolyte battery, the separator comprising a porous base material including a polyolefin and a heat-resistant porous layer provided on at least one surface of the porous base material and including a heat-resistant resin, wherein, when a thermomechanical analysis measurement has been performed by applying a constant load and increasing temperature at a rate of 10° C./min, the separator for a non-aqueous electrolyte battery satisfies the following conditions (i) and (ii):
 (i) at least one shrinkage peak appears in a temperature range of from 130 to 155° C. in a displacement waveform representing shrinkage displacement with respect to temperature; and 
 (ii) an extension rate in a range of from a shrinkage peak appearance temperature T 1  to (T 1 +20)° C. is less than 0.5%/° C. 
 
     
     
         2 . The separator for a non-aqueous electrolyte battery according to  claim 1 , wherein, when the thermomechanical analysis measurement has been performed, the porous base material has at least two shrinkage peaks in the temperature range of from 130 to 155° C. in the displacement waveform representing shrinkage displacement with respect to temperature. 
     
     
         3 . The separator for a non-aqueous electrolyte battery according to  claim 1 , wherein the porous base material has a plurality of shrinkage peaks, and an extension rate, in a range of from an appearance temperature of a shrinkage peak having the lowest appearance temperature among the plurality of shrinkage peaks to 200° C., is 0.5%/° C. or less. 
     
     
         4 . The separator for a non-aqueous electrolyte battery according to  claim 1 , wherein in at least one shrinkage peak, a shrinkage displacement amount at a maximum displacement point is from 1% to 10% with respect to a non-shrunken state. 
     
     
         5 . A non-aqueous electrolyte battery comprising a positive electrode, a negative electrode, and the separator for a non-aqueous electrolyte battery according to  claim 1  arranged between the positive electrode and the negative electrode, the non-aqueous electrolyte battery obtaining electromotive force by doping and dedoping of lithium.